I'm still fighting this thing. Is there anything else that I could check I will post the truck information if need be
I cannoy help of you are not specific with the info im asking for ,i have been working on these engines for 20 years now its hard to diagnose without being at the truck following is going to be a specific list of info i need to even think about helping . If you give me proper info which is gonna be actual numbers or actual psi i will help if not i wont , not being a dick or anything it just that i take my own free time like most everyone else on here to help when we can help.
Active fualt for speed sensor you need to fix that first then.
1. Fuel psi at idle and wide open throttle (normal doesnt cut it) if possible with an assistant driving truck watch fuel pressure at load especially in higher gears. My guages have about a 10 psi flutter in them when doing this if yours does also just average it. Should see no real drop under acceleration if it does please report what psi it dropped to also.
2. Does the odometer work adding miles as you drive if not you have a problem there as factory programing is to cut power 50 percent if it isnt seeing proper vehicle speed.
3.does your tool your using show data stream if so find throttle position data ensure that everytime you put accell pedal to the floor it says 100 percent ( i have had low power complaints from a pedal that would only read 99 percent changed pedal assy truck was good as new)
4.double triple check all hoses and piping for boost air have someone else look over it also sometimes a second set of eyes will see something you didnt.
5. Ensure that turbo you took off a blown up engine is good , spins freely no excessive play radially or end play usually a turbo is not reused off a bad engine .
6. While your playing with your j pro scanner or whatever it is take a picture of each fualt or the fualt code table with your phone and post please. I have mack books and actuall mack software not all scanners have good descrptions attached to the fualt.
7. Take picture of donor engine valve cover stickers so i can see exactly what model engine this is also becuase i am curious one of both sides of engine also.
8. When you adjusted those exhuast valves with the spring loaded push tubes . Proper procedure is to put feeler gauge under rocker use a special tool to tighten adjuster to 6 inch pounds then hold adjuster and tighten jam nut. I do this without the torque tool personnaly as long as the spring gets compressed so push tube is solid i then put my palm on back of rocker to keep spring compressed and see how my feeler guage feels , i have never had a problem doing it this way.
9 doesnt matter what way you you go thru this list this is what i would do to get started with your problem , starting with ensuring over head is adjusted correctly and that turbo is 100 percent. You are using the timing marks on the flywheel for adjusting the valves one cylinder at a time ? Just asking as i am unsure how familier you are with mack engines if your a full on mechanic or a driver that is also the mechanic.
